Steam-power plant



July l, 1930. .R. D. sPEAR 'STEAM POWER PLANT Filed May 15. 1929 y INVEN Kwaal.

@a @a ATTORNEY Patented July l, 1930 UNITED STATES PATENT OFFICE ROBERT DUROY SPEAR, OF ELIZABETH, NEW JER-SEY, ASSIGNOR TO FOSTER WHEELER CORPORATIOLL OF NEW YORK, N. Y., A CORPORATION OF NEW YORK STEAM-POWER PLANT Application tiled May 13, 1929. Serial No. 362,716.

My invention relates to steam plants and more particularly to steam plants in which steam is used for obtaining power, in which there are one or more prime movers such as steam turbines. v

Une purposeof my invention is to provide -an efficient utilization of steam in a steam plant. Another purpose of the invention is to provide a simple and ecient means for converting an existing steam4 plant into a steam plant of higher initial steam pressure.

In accordance with the invention, steam passing from a higher pressure prime mover to a lower pressure prime mover is reheated in a plurality of heaters through which the steam is conducted in series, the steam first being heated by high temperature steam which is condensed and then heated by the steam supply for the high pressure prime mover. In a steam plant 1n accordance with the present invention, steam is generated at high pressure and with high superheat in a high pressure steam generating unit. This generator may operate, for example, at 1200 pounds per uare inch pressure and provide highly super eated steam of a temperaturel of, for example, 800 F.

The steam generated would ordinarily pass direct to the higher pressure prime mover, but in accordance with this invention. the steam is passed through a heater in heat exchange relation with exhaust steam withdrawn trom the higher pressure prime mover, so that some of the. superheat in the high pressure steam given to the exhaust' steam. thereby siiperheating the exhaust steam. The high pressure steam with reduced superheat then passes to the higher pressure prime mover. From this rime mover the steam passes through what is termed a. dead-end heater and thence to the heater above described. This dead-end heater is preferably arranged and connected so that the high pressure, high temperature steam from the higher pressure steam generator is Supplied to it, the heating surfare of this heater being such that the exhaust steam is brought up to a point close to the saturated temperatur... of this high pressure steam, this reheating being done by the latent heat of the high pressure steam, which is condensed in this heater. In this way a certain amount of superheat is added to the exhaust steam. The temperature of the exhaust steam is still further raised in the heater heated by the steam sup lied to the higher pressure prime mover. n this wayl the exhaust steam is brought up to a fairly temperature. From this point thehigh ex -aust steam passes into the lower pressure main supplying the lower pressure prime movers or other steam consuming apparatus.

The accompanying drawing shows, more or less diagrammatically, a steam power plant layout embodying the present invention.

Referring to the drawing, reference character l0 designates a high pressure steam generator and superheater. This source of high pressure steam may provide steam of, for example, 1200 ounds per square inch pressure and 800 ture. This steam is supplied to the high pressure steam main 11. Steam flows from main 11 through conduit 12 and into thoroughfare heater 13. A thoroughfare heater` is one in which the heating steam passes through the heater without being condensed; in contrast to a dead-end heater in which the heating steam is condensed. The thoroughfare heater 13 ma);7 be of one of various types, but I prefer a heater of the general con struction indicated on .the drawing employing a number of tubes 14, extending between a supply chamber 15 and an `outlet chamber 16. and equipped with battles 17 to give a tortuous path ot flow for the steam to be heated around tubes 14. The heating steam for this heater passes through tubes 14 and out through chamber 16 and into conduit 17 i.shich supplies the steam to high pressure prime mover 18 which may be a turbine.

The exhaust steam from turbine 18 passes through conduit 19 and enters a dead-end heater 20 which may be of the same general construction as thoroughfare heater 13. Bales 21 are provided 'to ,btain a tortuoiis flow of the steam and an eicient hear. 11ans fer. From heater 2O the steam passes through conditi-i 22 and intaA the heated para temperaeefof thoroughfare heater 13. The steam passes around tubes 14 and is heated by steam in the same and-then asses through a connec- I tion 23 and into the lower pressure steam main 24.

Steam for heatin heater 20 is withdrawn from conduit llthrough Conduit 25, passes through tubes26 within the dead-end heater where it is condensed. The condensate is withdrawn through conduit 27 'and'is carried directly orindirectlyback to the boiler system of the plant. v

The lower pressure pressure prime mover 28 is connected to receive steam from conduit 24 through conduit 29, Prime mover" 28 may .also bea turbine and may, operate Y at an initial ,pressure of, or example, 400 pounds per .square inch. :This prime mover Y may lie-thehighenpressiire prime mover or. thebnly primegtmo'ver or one of. several, prime movers of ,.an existing'fplant -to' whch 4the present invention is;v applied.. l

Such anexisting plant includes the steam enerator,"30, supplying steam through con- (giuit 31, to, cond'uit 24, In applying the in-V ventionto a planti'nwhich'itis desired tol increase. the'- initial'stearn pressure, the` parts 10, 13, 18 fand, 20, with the inter-connecting condults, mayf be added and connected to the conduit 24. .This in effect chan .es conduit 24 from the higher pressure inainv to a low pressure main or4 a main of intermediate v pressure., It will be understood that steam generator 30,' while a. low pressure steam generator: so faras a plantembodying the invention is-concerned,may be a high pressure enerator with .reference 'to anexisting p anttowhich the invention is applied."

n applying this arrangement'to an existing plant, noVA changes need be made in the parts of, the existing plant. Reheating by sta es is obtainedwith the present invention wit out using reheaters heated by .flue ases. This givesa simple arrangement wit the A advantages and high eieiency of steam reheating 1n stages. p

instead of one thoroughfare heater and one dead-end heater, I may employ a number of each of these heaters.

It will be obvious that the invention may he carried out by any great variety 0f plant layouts and that steam plant apparatus may added and interposed in the various conduits without departing from the spirit or as scope e the invention.

l. A steam plant comprising, in combinaion, a source of: high pressure. superheated tea-m, a highpressure prime mover, alower pressure prime mover,a thoroughfare heatr a dead end heater, means to conduct from said source to the heaters in Aparallel, means to conduct steam from the thoroughfare .heater to the high pressure a@ prime mover, from the high pressure prime 2. A steam plant comprisinghin combination, a s'our'ce` of high pressurel superheated steam, a high pressure prime mover, a lower pressure prime mover, a thoroughfare heater, a dead-end heater, conduits for conducting steam from ,said sourceto. the heaters in parallel, a conduit for conducting steam from the thoroughfare heater to the high pressure prime mover, a conduit for conducting steam'fr'oml the high pressure prime mover to thedead-end heater, a con- Y y duit for conducting steam fromthe deadfendA heater to the thoroughfare heater, a

conduit for.; conducting 'steam from the thoroughfare heater to the lower pressure Aprime vmover anda conduit for withdrawing condensate from the dead-end heater,

' ROBERT DURO? 'SPEAK 

